TSG-6 Induce Apoptosis Of Human Hypertrophic Scar Fibroblasts Via Activation Of Fas/FasL Signaling Pathway

Background: TSG-6(tumor necrosis factor-stimulated gene-6,TSG-6)is a protective inflammatory reaction gene,which has high expression in many kinds of inflammatory diseases or processes similar to inflammatory.Recent studies suggest that TSG-6 exhibited anti-inflammatory and anti-scarring effects.However,the mechanism of effect of TSG-6 on scar remains poorly understood.Objective: The purpose of the experiment is to investigate whether TSG-6 affects the growth of human hypertrophic scar fibroblasts(HSF)via Fas/FasL signaling pathway.Methods: HSF were cultured and divided into three groups.Expression vector p LVX-Puro-TSG-6(carrying TSG-6 gene)was constructed and stably transfected to HSF named p LVX-Puro-TSG-6 group as experimental group,while expression vector p LVX-Puro(not carrying TSG-6 gene)was constructed and stably transfected to HSF named p LVX-Puro group as control group and untransfected HSF were also divided into control group.Expressions of TSG-6 in each group were then detected.MTT and flow cytometry assay were used to assess the effect of TSG-6 on the growth inhibitory and apoptotic status of hypertrophic scar fibroblasts.Finally,q PCR and western blot were used to measure the expression levels of Fas,FasL,FADD,caspase-3 and caspase-8 in each group.Results and Conclusion: The results demonstrated that the m RNA and protein of TSG-6 in experimental group were significantly increased compared with controlgroups,but there were no significant difference between control groups.The apoptosis rate in experimental group was significantly higher than control group,and the cells in experimental group had a markedly reduced growth rate.The expression levels of Fas,FasL,FADD,caspase-3 and caspase-8 were significantly raised in experimental group.In conclusion,the high expression level of TSG-6 may induce the apoptosis of human hypertrophic scar fibroblasts via activation of Fas/FasL signaling pathway.